Insulator



Mircb 1933- l J. H. HERTNER INSULATQR Filed Feb. 16, 1932 Arm zmers Patented Mar. 7, 1933 STTES PATENT OFFICE" JOIIN H. HERTNER', 01 LAIEWOOD, OXID, ASSIGN 0B '1'0 m BIB'INEB EIBI'BIC 00H- 1AN'Y, 01' CLEVELANID, OHIO, A OOBPOBL'IIOII'DI' OHIQ INSULA'IJOR Lpplication flled l'ebruary 18, 1832. Berta! li'o. 583,298.

This invention relates to an electrical insulator and p'articularlyto electrical insulation having especial utility in connection with elcctxical machinery or deviccs wherein it ls necessary to insulute against low voll:- ages. An illustration of the necessity for the' use of such an insulation was found in the fieldwindings of' generators und motors where bare eo per ribbon is wound on edge 0r on the flat or series or interpole coils and wherein the heat developed v is relatively high, althoug'h it will be realized that there are numerous other instances wherein an insulator cmbodying the present invention ma be advantageously uscd.

n objcct of the invention is to provide an =;lectrical insulation which is mechanically strong am] safe, yet of such character as to occupy a minimum amount of space.

Another object is to provide an electr1cal insulation Which is substantially unafl'ected loy hi h temperatures.

A Eurthex objcct is to provide an electrical insulation which, while mechamically strong, is extremely thin und therefore can be ac coxnmodnted in a small amount of space.

A still further object is to rovide'an electrical insulation Which may e used for the additional purposc of providng for heat radiation.

Another additional object is to rovide an electrical insulxition wh1ch may readily andfie (z;m mically manufactured and easily a e Eurther and additional ob'ects of the invention will appear hereina r du the following detailed description of th6 invention.

The inyention in its'broad aspect contemplatas an electrical insulation formed of metal liaving thereon a non-conducting coating.

In order to more fully desc:ibe the invention and thc manner in which the insulation may be used, reference should be had to the accompanying drawing and the description based thereon that is to follow.

In the draw' Fi 1is a l :rspective view of an edga wou nd coil, w erein the turns cf oopper ribbon insulated f rom Fig. 5 is a sectional view 011 an enlar ed scale taken substantiall online 5--5 of ig.

3 looking in the direct1on of the arrows.

Fig. 6 is a sectional view of a. flat wound 0011 and is taken substantially on line 6-6 of Fig. 7, looking in the directon cf the arrows; anci Fig. 7 is a sectional view of a flat wound coil and is taken substantially on line 'Z7 of Fig. 6, looking in the direction of the arrows.

It is important that-insulation, which is useclin various forms of electrical machinery or devices, be mechanically streng to insure it against being broken, but at the same time such insulation must necessarily be thin in order to occupy a mininium amount oin s ace. In attaifiing the provision of an msulation that posses'ses grea t mechanical strength, but which is not bulky o1 thick I ropose to employ an insulation formed f m metallic strips having thereon a thin non-conducting coating. The

metallic strips preferably should be axtremely thin, but it will be understood that the th1cknem of the strips ma be governed aocording 170 thc various n of the particular instanoein. which they are used, such as the spaoe in which the insulation is to be arranged and the vprassure to which it will be subjected in u se and also by the further considerati on of the prioe of tlie material. The non conducting coating that is applied to the stripg may ta ke various forms, such as a thin'coatmg of v1treous enamel, a ooating cf phosphate of iron, or any other good noncondnct1ng ooating. AI: the present timo.it

'1t 1s not necessary in everi'1 ploy the catalyst. The

is believed that a non-conducting coatiixg formed of phosphate of iron or other nonoxidizing coating is thc pref erable coating to be applied to the strips and for that reason the coating will be so described herein, itbe ing understood, however, that the .invention preferably cxtremcly t hin steel strifis, are

cut into' the pro -r sha1ie and are then imm crsed in orsu jectted tothe action of a. bath combosedof a dilute s0lution of phasphoric acid, having in some instances, a s'uitable ca talyst therein, such as ferr0us phosphate, iron-filings or the like', although instance to emosphate of iron c0ating might also be app ied by passin an ;(alectric current thr0ugh an electrolytio ath acid und having the phosphat4'a 0 ing can be varie metallic blanks or strips. The thic formed of a. dili1te solution of hosphoric F'iron coating clectro-chemically deposited u on th e ess of phosphate of iron coatm accordance with the conditions to which the insulat ion will be subjected in use. The present invention ddes not include broadly the cojating cf metal with a. phosphate of iron coating for general use,- since this is well known in the art, but it does include the provisiofn of an electrical insulation in the form of metallic blanks or strips having thereon a non-coriducting coating such as a phosphate cf iron coatin l In t e accompanying drawing there is' illustrated in FigsQ 1 to 5, inclusive a coil having a. Pole piece or core 10 upon which thc non-conductin a continuous ribbon of bare copper 11 is wound on edge, insulating pieces of fabric 12 being interposed between the core 10 and the inner edges of the copper ribbon 11 und bent lateral y over the outvermost turri of the cop r r1bbon as indicated at 12a and under t e innermost turn of the ribbon, as indicated at 12b. There is also provided, between the outcrmost turn cf the ribbon and the laterally bcnt portion 12a of the fabric 12, an oval pieceof 'fabric 13 while annular strips 14 of ber or other suitable material extend between the portions 12b cf the fabric 12 und foot portions 15 of the core 1 and upwardly along the outer side of the coil, such annular strips 14 extending .longitudinally of the coil for only a portion of its length. Since the construction cf the co1l r so fo rms no partof the present invent1on, and 1s well known in the arta more detailed d ription of such construction is hnnecessar y lierein and it should suflice to say that the coil illustrated in Figs. 1 to 5, inclusive, of th e .drawing may b e of any well known construction wherein a continuous copper ribbon is wound 011 edge about a.

-core or pole piece'.

In adapting the insulaition of the present invention for use with a coil, such as shown in Figs, 1 to 5, inclusi vc it is proposed to -cut thin metallic strips 16 iuthe form cf half ovals, of such size that When the strips am assembled in 'the coil, each end of each half may overlap the ad'acenti end of thc other half, as clearly in i'cated in Figs. 3 and 4. The semi-oval strips after being cut are then provided with the non-cdnducting coating, such coating being indicated at 17 in Figs.3 and 5 and preferably being a phosphate of iron coating. As previously mentioned, the thickness of the metallic strips, which are preferably steel strips, may vary to suit the diflerent c0nditions of 5 use .while corre'spondingly the thickness of the non-conductingboating may also vary. Thestrips with th e non-conducting coating thereon are inserted edgewise between the turns of the copper ribbon coil 11, as clearly indicated in F igs. 1 a-nd 2, \tha ends of eac h strip' overlapping thends of its cooperating strip, such 'cooperating stri s forming together an oval cf substantial y the same size or configuration as the turnsof the coil. The width of the strips may be such that their outeredges will -project a short distance outwardly cf the outer edge of the copper ribbon 11, so that said strips will serve the additional purpose cf radiating fins that will carry ofl the heat 000asioned by the energy loss in the coil.

In Figs. 6 and 7 there is illustrated a coil of thaflat wound type and in which is employed insulation according to the mvention. Referring to Figs. 6 an 7 the core of the coil is indicated at 18 while the bare copper ribbon flat wound thereon is ii1dicated at 19. The insulation is indi0ated at 20 a11d is a thin ribbon formed of thin metal, such as steel, and having thereon thc pho'sphate coating previously referred to and applied in the same manner. In constructing the coil the copper ribbon 19 and the insulating strip 20 am wound simultaneously upon the core 18, so that between each turn of the copper ribbon 19 there is a. turn of the insulation 20. The width of the insulating strip 20 may be slightly greater than the width of the copper ribbon so that the edges of the insulatmg strip lie out- Wardly of the edgcs of the copper ribbon in order to carr ofl' the heat-produced in the coil, as in t e construction illustratecl in Figs. 1 to 5, inclusive.

It will be seen that the coated strips proresent vi lo m insulntion which, it i8 commainly ofmotal auch as steel, will 'nve graut meclmnical stre h und will not be likely to be aocidentully rohen. It will further be noted tha.t sinoe the atrips und th3a non-oonducting coatingthereon are relatively thin that the insulvtion does 'not applied have been illustrated und described herein, it should be understood that the inoocupy much spaoe, but at tho samq time possesses graut mechanical strength. The msulation althoug*h being formed mainly 013 metal is substantially unnflected by the high temperatures Produoed bythe-energy loss und, sinca the insulation is of metal it man? be' readily applied by inserting e same edgewise betweon the turns of the coil or by winding the same upon the core in between the turns\ of the coil as in the flsat wo1ind type shown in 6 und 7. t

hough wveral preferred embodimenls of= the uses t0 Whichthe inventionmay be vention is Susoeptible ofvarious other uses,

modifications und adaptations within the scqpe of t he appende2d claims.

Having thus desc'ribed my invention, I

-claim:

1. An ele0trieal insulator comprising ametallic strip having thereon a metallic phosphate poating. A

2. An electrical insulator comprising a steelstr.ip having thereon .a phosphate of iron coatmg.

. 3. In 'c ombination an electrical coil compr1sm a. eure, a conductmg material wound on sai core, und insula tors formed of metal having a non-conductii1g coatin arran d between the adjacent turns of sa1d matenal.

4. In combination, an electrical coil comp ris' a core, aflat ribbon of conducting mater1al wound thereon, and flat insulators formed of metal having a non-conducting coating arranged between the adjmnt turns o f said material.

5. In combination, an elactrical coil comind eoonomically manu%acture. by stampmg or other rocesses und is easily eonducting mntorisl wound thereon on sge,

und insulators formed of flat =metal stnps haiving 15 non-conducting coating arranged between the adjsoent turns cf sa1d matenal, said strips being arranged in cooperating pairs with the adjaoent ends oi the 'stri of each pait overlapping.

8. In oombination, an electricul coil comprising a. oore a flat copper ribbon wou'nd Ihereon5 und insulation arranged between th'e adjwcent turns 0f said ribbon, said insulation being f0rmed of thin strip metal havin'g a ch emically' deposited phosphate of. irdn coating thereon.

9. In combiixation, an electrical coil comprising a core a flat ribbon -of conducting matenal wound thereon with its flat side encircling said core, und a, metallic' strip having a npn-conducting coating thereonarranged between the adjacent turns of said materml und 'insulating the sqme from each other.

10. In combi'nlztion, an 6lectrical coil my signature.

JOHN H. HERTNER.

prising a:core, a flat ribbon of conducting material wound thereon on edge, und flat insula.tors formed of metallic stri haviug a. non-conducting coating arrange between the adjacent tums of said material.

6. In combination, an electrical coil comprising a core, a flat ribbon of conducting mat enal wound edgewise thereon, und flat 'insuhtors formed of metal st-rips having a non-conducting coating thereon arranged between the ad-jacent turns of said material, said strips' .b(aing of greater wid&h than the Width of said material und being insertecl edgewise with respect w the eure and hav- 'ing their outer edges lying laterally out-- wardly of the outer edge cf said material. 7. In combination, an electrical coil comprising an elongated core, a flat ribbon of 

